Hybrid epoxy composites reinforced with bamboo fibers and carbon nanotubes: Enhanced mechanical properties and flame retardancy for sustainable applications

Abstract This study focuses on the development of hybrid epoxy composite materials reinforced with bamboo fibers treated chemically using Ca(OH) 2 and advanced nano‐additives such as multi‐walled carbon nanotubes (MWCNTs). The bamboo fibers were treated with Ca(OH) 2 solutions at concentrations of 3%, 5%, and 7%, with 5% identified as the optimal concentration. The EP/BF treated 5% Ca(OH) 2 /0.2% wt MWCNTs composite exhibited superior mechanical properties, including a tensile strength of 179.69 MPa, flexural strength of 189.69 MPa, compressive strength of 229.69 MPa, and an Izod impact strength of 29.69 kJ/m 2 . The flame‐retardant performance was also significantly enhanced, with a limiting oxy index (LOI) value of 26.3% and a UL‐94 HB burning rate reduced to 17.28 mm/min. SEM analysis of the material's morphology revealed a uniform structure with no phase separation and strong adhesion between the bamboo fibers, nano‐additives, and epoxy matrix. This research demonstrates that green chemical treatment with Ca(OH) 2 instead of traditional NaOH, combined with nano‐reinforcements, not only improves the mechanical properties and flame retardancy but also enhances the overall performance of the composite, making it suitable for sustainable industrial applications.